Evidence for a sequential transfer of iron amongst ferritin, transferrin and transferrin receptor during duodenal absorption of iron in rat and human

Table 2 Summary of in situ grading of sequential autoradi-ographic and immunohistochemical staining signals

Radioactiveiron/protein	Iron status	Basal	5 min	15 min	30 min	2h
59Fe	ID	-	SUR+	IE+++	IE+++	-
	OL	-	SUR+++	IE±	IE±	-
Tf	ID	IV±	IV++	IE+++		IE+
				IV++		IV++
	OL	IV±	IE±	IE±
			IV±	IV±
TfR	ID	SUR±	SUR++	IE++	IE+	SUR±
	OL	SUR±	SUR++	SUR+	-	-
Fe	ID	IE±				IE±
		IV±	-	-
	OL	IE±	-		IE±	IE±
						IV+++

Tf: transfferin; TfR: Transferrin receptor; Fe: Ferritin; ID: Iron deficient; OL: Iron overload; IE: Intra epithelial; IV: Intra vascular; SUR: Surface; Grading +: minimal staining; ++: good; +++: intense; –: nil.